Process of making asphaltic building blocks



alkaline hydroxides, or car onates,

Patented June 15, 1948 txamme:

PROCESS OF MAKING ASPHALTIC BUILDING BLOCKS August Holmes, Craniord, N. J., and Joseph C. Roediger, Brooklyn, N. Y., assig'nors, by mesne assignments, to Standard Catalytic Company, a corporation of Delaware No Drawing. Original application November 7,

1939, Serial N0. 303,316.

Divided and this application December 8, 1944, Serial No. 570,208

2 Claims.

. This invention relates to improvements in the methods of treating soils for the manufacture of blocks for use in curtain or hearing wall construction, or as flooring blocks. These improvements may also be applied to the monolithic laying of soil-asphalt mixtures for low cost roadways, now termed soil stabilization."

It is well known that dwellings may be made of earth or clay earth which is perhaps the material used in the first buildings erected by man, but the objections to structures of such material were that they often washed away during long, rainy seasons, were susceptible to infestation by rodents, vermin, and the like, and in many cases developed cracks due to stresses set up by climatic changes. Bricks were later used which were prepared by mixing clay and straw and allowing the moulded mixture to harden by exposure to the sun. In the development of brick manufacturing methods, artificial heat was used in order to obtain a stronger material which would resist the effects of water and thereby be an improvement over the ordinary clay-straw brick.

Building blocks have been manufactured in recent years from a mixture of soil, selected or adjusted to have a satisfactory grading and a suitable content of clay, with the proper amount of cutback asphalt or emulsified asphalt. This mixture which generally contains water to facilitate the thorough incorporation of the asphaltic material is compacted into blocks of the desired size using known methods of compaction. The finished block is then cured by natural or artificial means so that it may obtain a suitable strength before use in construction.

It is an object of this invention to manufacture building blocks using as the major proportion of the material clay or soil which is available close to the locat'icfi' where they are to be manui'actured and thereby economizing by using the cheapest material available in that locality.

According to this invention, soil is mixed with a limited amount of an aqueous solution of an alkaline material, such as water-soluble soaps,

phosphate, sodium s1licate, etc. to prepare a plastic mixt'ure of the soil. Lime may be added to the plastic mixture.

An asphalt binder containing a reactive agent such as oleic' acid, naphthenic acid, etc. is then added to the plastic mixture. The asphaltic binder may be a combination of a fiux oil and powdered hard as halt having a softening point of 150 to 450 F., the latter added separately; an asphalt having a softening point ranging from triso ium 2 90 to 150 F.; a cutback asphalt, or an asphaltic emulsion. The mxture is then poured into mo and cured. It may be subjected to pressures up to 3000 pounds per square inch, ii desired. If the blocks prepared according to this method are to be exposed to moisture in sections of the country where the rainfall is substantially high, heat may be used to accelerate the curing of the block.

Likewise, the clay or soil may be first impregnated with about 1% to of a water solution f a metallic sal such as lead nitrate, iron chlor i c i e, Eon sfilfate, etc. mt of salt in solutimbly about 10%, although 2% to 25% solutions may be used. The soil, after thorough mixing, is treated with 2% to of a cutback asphalt, preferably about 5% by weight.

e on ack asphalt contains from 40 to 90% of an asphalt having a softening point ranging m from 90*F'Ito as high as 150 F. The cutback or the asphalt solution contains agents such as Qity acils, metallic soaps, heptadecylamine, etc. The treated soifmmed with the cutback asphalt is then poured into moulds and subjected to pressure or tamping. The pressure used may be up to 3000 or m'6re pounds per square inch, or a pneumatic tamping device may be used.

The building blocks on removal from the moulds are generally cured, with or without the aid of artificial heat, to remove volatile materials.

lime, plaster of Paris, etc., which will take up the wa er an orm ydrated compounds which 0 developed additional strength in the mixture over that obtainable by the simple evaporation of water from the mixture. The finished block will have a high earlier strength if treated with a hydrating material.

For example, soil is treated with a suitable amount of water 1n order that the soil may have that water content permitting satisfactory subsequent incorporation of the asphaltic binder. To this moistened soil is then added the as halt 5o binder which may consist of flux oil Tim asphalt, cutback as halt or emulsifig asp TEE, together with a wetting agent. About 3 to 10% of the asphalt bin er is used. The soil and the asphalt binding material are thoroughly mixed,

as after which is added a suitable amount, usually in the range of 1 to 5%, of dry cement, burnt lime um, or other ra in settin aterial W'com me with the major portion of the water present in the soil. It is preferable in certain cases to add the hydrating setting material to the moistened soil before the addition of the asphalt binding material. The resulting mixture is then placed into moulds and subjected to a pressure of at least 50 pounds per square inch.

This application is a division of our U. S. application Serial No. 303,316, filed November 7, 1939, now Patent No. 2,386,163, granted October 2, 1945.

We claim:

1. 'A process of manufacturing building blocks, curtain wall blocls and floor blocks which comprises mixing in a cold state soil and a fluid vehicle containing a wetting agent of the class consisting of trisodium phosphate and sodium silicate to form a plastic mass, adding an asphaltic bonding agent to which had been added heptadecyl amine to the plastic mass and molding the mixture into blocks.

20 Number REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 2,386,163 Holmes Oct. 2, 1945 

